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Kim Valenti is a hotshot codebreaker, when something she cracks turns out to be dismissed by her superiors she goes to investigate. She ends up kidnapping Lex Tanner (a bomb disposal expert), who she knows more from online than reality to help her disarm the bomb. When this turns out to be reality rather than imagination he joins forces with her to track the culprits down.
Reads almost like two linked novelettes rather than one full book it's a fun read.